Art of scanning and reproducing matter



A ril 3, 1934. -R. E. NAUMBURG ART OF SCANNING AND REPRODUQING MATTERFiled April 10, 1931" 4 Sheets-Sheet 1" fill 2 13a?" 1 R. E.- NAUMBURGART OF SCANNING A ND REPRODUCING MATTER April 3, 1934.

Filed April 10, 1931 4 Shets-Sheet 2 Ap 3, 1934. R. E. NAUMBURG ART OFSCANNING AND REPRODUCING MATTER 4 Sheets-Sheet 3 April 3, 1934. R. E.NAUMBURG 7 1,953,307

ART SCANNING AND REPRCDUCING MATTER Filed- April 10, 1931 {Sheets-Sheet4 .S'akruhaza cell -Patented Apr. 3, 1934 UNITED STATES PATENT OFFICEART OF SCANNING AND REPRODUCING MATTER 7 Claims.

which can readily be practiced by blind people so that their readingneed not be confined to the limited amount of printed matter publishedin Braille and the like but may be extended to any and all printedmatter at moderate cost and to reproduce the printed matter in a formsuch as Braille, Moon type and other embossed type with which many blindpeople are familiar and by which the reader may comprehend a letter orgroup of letters by a single touch sensation.

Other objects are to facilitate the initial positioning of each page orline of printed matter by the sense of touch preparatory to reproducingthe page or line; to vary the size of the reproduced characters at will;to afford a rapid rate of reproduction with little delay in shifting tosuccessive lines; to afford means for reading printed matter by touchwithout reproducing the matter, preferably without disturbing thereproducing means in case such means are incorporated; to avoid falseindication or reproduction, particularly while shifting from one line tothe next succeeding line; to provide an ii-- proved scanning disk usefulfor blind reading and other purposes; to provide inexpensivereproduction, with a medium which can be used repeatedly as a temporaryrecord and/or can be readily converted into a permanent record; andgenerally to improve the art to'which this invention relates.

For the purpose of illustrating the genus of the invention a typicalembodiment is shown in the accompanying drawings in which Fig. 1 is atop plan view;

Fig. 2 is a partial front elevation;

Fig. 3 is a diagrammatic view illustrating the scanning disk;

Fig. 4 is a top plan of the reproducing and/or feeler mechanism;

Fig. 5 is a side elevation of this mechanism;

Fig. 6 is a circuit diagram;

Fig. 7 is a face View of the reproducing medium In certain aspects thewith typical characters -reproduced thereon; and

Fig. 8 is a section of the reproduction sheet shown in Fig. 7.

The particular embodiment of the invention chosen for the purpose ofillustration comprises two groups ofmechanism, the one at the lefthandside of Fig. l cooperating with the book or other printed sheet toproduce current variations corresponding to the printed characters andthe other, shown at the right-hand side of Fig. l, reproducing theprinted matter on sheet material in the form of Braille characters inresponse to the current variations. The first group of mechanism forscanning the subject matter is, with certain exceptions referred tohereinafter, essentially the same as disclosed in the aforesaidapplication.

In general this scanning mechanism comprises a support 1 (preferablysuch as shown in said application) for supporting a book or otherprinted matter in horizontal position, a glass cover plate 2 for holdingthe exposed pages of the book substantially in a horizontal plane,abracket 3 carrying a half nut 4 meshing with a worm 5 forv advancingthe book one line at a time in response to a ratchet handle 6, the bookcarriage being retracted to start a new page by lifting the half nut 4out of engagement with the worm 5 and reengaging the nut at a differentlocation of the worm. The optical mechanism is mounted on a carriage '7reciprocatable back and forth from left to right on the stationary guide8, the carriage having a rack 9 meshing with pinion 10 on shaft 11. Theoptical parts comprise a lightsource 12, three lenses 13, 14 and 15, thelens 15 being adjustable longitudinally of the optical axis by means ofa rack 16 and a pinion 17 to accommodate letters of different sizes, acontinuously rotating scanning disk 18, a right-angle reflecting prismfor reflecting the light rays downwardly, lenses in the vertical portionof the optical path, these lenses being mounted as indicated at 20 inFig. 2, and a selenium cell 21 mounted on the support 20 to receive thelight reflected from the printed page, the cell having a central opening22 to permit the passage of the light rays to the printed page as fullydisclosed in the aforesaid application.

As illustrated in Fig. 3 the scanning disk 18 breaks up the light intosix intermittent beams or rays which are incident to the printed pagealong lines a, b, c, d, e and f spaced to intersect the letters asindicated. According to this invention the dimensions, longitudinally ofthe row, of the perforations in the scanning disk and the forationstransversely of the rows.

spaces tnerebetween, are approximately equal, whereby the currentvariations produced in the electrical circuit later to be described areapproximately sinusoidal. The perforations of each row are alsostaggered transversely of the row, preferably to such extent that theinner edges of alternate perforations lie approximately in the sameline. In this way the scanning lines a, b, c, d, e and f more constantlyintersect the desired portions of the letters notwithstanding inaccuracyin the alignment of the letters, without undesirably increasing thewidth of the perv Moreover, for reasons not fully understood, thefeelers or strikers hereinafter described operate more uniformly andreliably if the perforations are staggered.

The reproducing mechanism shown at the right-hand side of Fig. 1 andillustrated more in detail in Figs. 4 and 5 comprises a carriage 23reciprocatable back and forth from left to right on rollers 24 (Figs. 4and 5) which roll on stationary guides 25. The carriage has a projectingarm 26 threaded to mesh with a worm 27 for reciprocating the carriageback and forth. Mounted on the carriage 23 are six electromagnets 28a,28b, 28c, 28d, 28c and 28] which are controlled by the light raysscanning along the lines a, b, c, 03, e and f (Fig. 3) respectively.Each magnet has an armature 29 held in retracted position by a spring30, the retracted position being adjustable by a screw 31. Pivotallyconnected to the free ends of the armature levers 29 are vertical rods32 which are guided in their up and down motion by an upward extension33 of the carriage 23. The upper-ends of these rods are rounded toconstitute strikers or feelers as hereinafter described. As shown inFig. 5 the second, third and sixth of these rods (counting from left toright) are in elevated position and the other three are in the loweredposition occupied when the corresponding magnets are energized.

The sheet material to be embossed by the strikers 32 is fed from a roll34 upwardly and rearwardly around a curved guide 35 having, in its upperhorizontal portion, an elongate slot 36 corresponding to the path ofreciprocation of the strikers 32, The sheet material S is fed upwardlyand to the rear by means of rollers 37 and 38, the lower rollers 37being mounted on shaft 39 and the upper rollers 38 being mounted on arms40 pivoted to swing upwardly about the shaft 41 journaled in brackets46. While a line of characters is being embossed on the sheet S by thestrikers 32 the portion of the sheet brid ing the elongate slot 36 isheld taut bypressure pads 42 and 43 which are preferably fared withchamois skin. The pad 42 is supported at each end by a bracket 44 fastto the shaft 41 (Fig. 1). And the pad 43 is supported by a plate 45 fastin a slot in the shaft 41. Thus when the shaft is rotated in acounterclockwise direction (Fig. 5) both pressure pads are lifted fromthe sheet S. The mechanism for rotating the shaft 41 comprises a leverarm 4'7 fast to the end of the shaft (Fig. 1) and linkage 48interconnecting the arm 47 with the handle 6. This linkage comprises arod 49 which carries a pawl for rotating the shaft 39 of the lower feedrolls 3'? through a ratchet wheel 50 fast on the end of the shaft.

The reciprocating scanning carriage '7 and the reciprocating reproducingcarriage 23 are actuated synchronously by motor 51 which continuouslydrives shaft 52 by a belt 53. The worm shaft 27 carries a friction disk54 which cooperates with a friction roller 55 threaded on the shaft 52to screw back and forth between two limiting positions near the centerand periphery of the disk 54 respectively. The motor 51 is a reversiblemotor and suitable means (not shown) controlled by one of thereciprocating carriages or associated parts are provided for stoppingand/or reversing the motor at each end of the reciprocatory movement ofthe carriages. While the carriages are advancing from left to right theroller 55 engages the disk 54 near the periphery of the latter as shownin Fig. 1 to produce relatively slow movement of the carriages andduring the reversed travel of the carriages from right to left theroller 55 engages the disk 54 near the center of the disk to produce aquick return of the carriages, it being understood that when the motor51 is reversed the roller 55 automatically threads along the shaft 52from one of its extreme positions to the other. The worm shaft 27 whichdrives the reproducing carriage 23 is interconnected with the shaft 11which drives the scanning carriage '7 through gearing 56 and a clutch57, the clutch being provided to disconnect the scanning carriage whilethe latter is being, initially adjusted at the beginning of a new pageor sheet of printed matter.

The circuit arrangement illustrated in Fig. 6 is substantially the sameas that disclosed in the aforesaid application in which 21 isthe-selenium cell connected through an amplifier to a circuit containingtransformer primaries A, B, C, D, E and F corresponding to the similarlydesignated lines of Fig. 3 and magnets of Figs. 4 and 5. With eachprimary is associated a secondary circuit tuned to one of thefrequencies determined by the number of perforations in each row of thescanning disks (the numbers preferably being 85, '71, 59, 47, 3'7 and 29counting from the peripheryof the disk toward the center) one suchsecondary being shown in association with primary A. Each of the sixsecondary circuits comprises a tuning condenser C, a three-elementvacuum tube V, a feed-back coil Band a relay through which thecorresponding magnet 28 is actuated. This relay is preferably of thetrigger type (suchas the General Electric thyratron) which effects quickand large current changes in the magnet 28 in response to slight currentvariations in the input circuit. The use of regeneration in the filtercircuit serves to emphasize the desired frequency to theexclusion ofothers. When the scanning rays are incident to white paper or otherreflecting surface the flow of cur- 1 rent increases in the seleniumcell, also in the trigger tube and also in the magnet 28, therebyretracting the corresponding striker 32. When the scanning rays areincident to a printed line or other non-reflecting surface comparativelylittle current flows through the selenium cell and consequently thetrigger tube completely stops the flow of current through the magnet 28,thereby permitting the spring 30 to advance the corresponding striker32.

Thus it will be evident that the six (more or less) intermittent lightbeams produce in the selenium cell circuit a composite currentcomprising six superposed waves and that the tuned circuits filter outthe six waves into the individual circuits containing the trigger tubesor other devices for manifesting current variations. It will also beunderstood that any suitable filter system may be employed includingtuned relays or magnets.

From the foregoing it will be understood that a line of printing isreproduced on the sheet S in the form of raised characters in thefollowing manner. When one of the six light rays or beams crosses ablack line the corresponding striker 32 is advanced to produce anindentation in the sheet S. If the printed line be vertical andrelatively thin the striker is advanced only momentarily to produce adot on the sheet S. If the line of the printed character extendshorizontally for a considerable distance, such as the top of a capitalT, the striker is held in advanced position for a considerable intervalof time depending upon the length of the line, thereby producing in thesheet S an indentation in the form of a dash. Thus the letters 0, f, tare reproduced in the form illustrated in Fig. '7.

The reproducing carriage is preferably advanced ata rate several timesas fast as that of the scanning carriage in order to permit enlargementof the characters horizontally (as well as vertically) and in order toincrease the spacing between the embossed characters for more facilereading by touch. For the purpose of still further increasing thespacing between the embossed characters, particularly where theembossing is in the form of dashes rather than dots, I preferablyprovide means whereby each striker 32, when indented into the sheet S,may lag behind the reproducing carriage 23 until it is withdrawn fromthe sheet, whereupon it snaps forward to regain its normal positionrelatively to the carriage longitudinally of the path of travel of thecarriage. In the illustration this gap wideningmeans comprises guideslots 60 (Fig. 4) in the carriage extension 33, the slots extendinglongitudinally of the path of travel of the carriage and the strikers 32being pivoted on the lever arms 29 to swing lengthwise of these slots,spring 61 being provided normally to hold the strikers at the forwardends of the slots and to snap the strikers back to these ends whenretracted from the stationary sheet S. This arrangement has the furtheradvantage that thick and thin lines as, for example, vertical strokes ofdiiferent shading, are reproduced with aproximately equal thickness,this fact affording, according to actual experience, an instrumental aidto the blind in reading the embossed sheets.

The sheet S is preferably in the form of aluminum or other metal foilabout two-thousandths of an inch thick embossed with minuteprotuberances which project about one-thousandth of an inch and whichare much smaller in transverse dimensions than the correspondingdimensions of the rounded noses of the strikers 32 (e. g. 100 to theinch), whereby the sheet has substantially no tendency to rupture whenimpacted by the strikers 32 particularly when indented by the strikersoppositely to the protuberances. By using such embossed foil the sheetmay be indented by the strikers 32 merely by folding the sheet taut inthe region of the strikers and without backing the sheet with a platen.of the sheet are accessible for touch reading by the operator as soon asthey are formed. Thus the operator may read the characters as they arebeing reproduced and after the roll of foil is exhausted it may beironed out for repeated use. By ironing out the foil with mandrelshaving embossing protuberances the aforesaid minute pro- Consequentlythe embossed characterstuberances may be reembossed in the foil in theironing process.

On the other hand if the sheet of embossed characters is to be preservedfor repeated use the characters may be permanently upheld by applying tothe sheet a composition which sets when dry. Any one of manycompositions may be employed depending upon the degree of permanencydesired. Typical examples are shellac, plastic wood and tile cementdissolved in plastic wood solvent. The composition is preferably appliedto the back of the sheet and when using plastic wood or the like theindentations may be largely or entirely filled.

Instead of using foil 1 may use a fine mesh screen, preferablycomprising several superposed registered sheets or bands of screening,with pins snugly fitting in the screen perforations so that they may beengaged by the strikers to project beyond the face of the screen.Preferably these pins normally project from the rear of the screen forengagement by the strikers so that the strikers need not enter theperforations. For repeated use the pins may be pressed back into thescreen by a roller or the like; and the screen (as well as foil) may bein the form of an endless belt which is rolled in advance of the strikerpath for repeated use.

The width of the sheet S and its position relative to the path of travelof the reproducing carriage 23 is preferably such that the strikers 32are exposed at one or both sides of the sheet at one or both ends ofeach reciprocation, preferably at the left hand end, whereby the tips ofthe strikers may be touched directly by the tip of the finger whileinitially adjusting the position of the lines of printed matter relativeto the path of reciprocation of the scanning carriage. It is alsodesirable to provide manual control means for the motor whereby thecarriages may be reversed at any point in their travel.

In order to prevent the strikers 32 from operating on the return strokeof the carriages from right to left means may be provided to render theelectrical devices unresponsive to the printed matter during the reversemovement. The preferred means, illustrated in Fig. 2, comprises areflecting shutter mounted on arms 71 to swing back and forth about thepivot 72. Also fast to the pivot pin '72 is a second arm '73 the lowerend of which slides over a soft track 74 of rubber or the like on astationary guide 8. The distance between the pivot 72 and the face ofthe soft track '74 is somewhat less than the length of the dependingportion of the arm 73. Thus when the carriage reverses its movement thearm '13 gouges into the soft track and is caused to swing past deadcenter to a corresponding position on the other side of the verticalplane of the pivot therein and then slide freely over the surface of thesoft track until the carriage is again reversed. As shown in Fig. 2 thecarriage is traveling to the left and the light is continuouslyreflected from the shutter to the light sensitive cell, therebymaintaining magnet 28 energized during the return movement. When thecarriage reaches the left end of its path of reciprocation and reverses,the reflecting shutter automatically swings to the left out of the pathof the light rays. This shutter preferably has a difiusing surfaceinstead of a mirror surface, ordinary white paper or cardboard beingsuitable.

I claim:

1. Apparatus for embossing sheet material comprising means for holdingthe sheet at each side of an elongate space, strikers for indenting thesheet at points distributed transversely of said space, and means forproducing relative movement between the strikers and sheetlongitudinally of said space, said strikers being yieldingly mounted tofollow said movement while indented in the material.

2. Apparatus of the character referred to for embossing material,comprising a striker for indenting the material, and means for producingrelative movement between the striker and material, the striker beingyieldingly mounted to follow said movement While indented in the material.

3. Apparatus of the character referred to for embossing material,comprising a striker for indenting the material, means for producingrelative movement between the striker and material, the striker beingpivotally mounted to follow said movement while indented in thematerial, and a spring for returning the striker to normal position whendisengaged from the material.

4. The method of indenting sheet material from one side to form on theother side raised characters legible through the sense of touch, whichcomprises holding the sheet material taut and indenting the tautmaterial, whereby the raised characters may be read by the sense oftouch during the process of forming the characters.

5. The method of indenting sheet material from one side to form on theother side raised 6. Apparatus for indenting sheet material from oneside to form on the other side raised characters which may be readthrough the sense of touch, comprising means for holding the sheetmaterial taut and means for indenting the taut material, the latter sideof the sheet being unobstructed adjacent the indenting means so that thecharacters may be read by touch during the process of forming thecharacters.

'7. Apparatus of the character referred to comprising means carryingsheet material, an indenting striker relatively moving along the surfaceof said sheet material and yieldable in the direction of said relativemovement, whereby said relative movement is interrupted if said strikercontacts with said sheet material, means limiting said yielding motion,whereby said relative movement is resumed upon said striker contactingwith said limiting means after a certain period of time, and means forreturning said striker to normal position upon interruption of itscontact with said sheet.

ROBERT E. NAUMBURG.

